If you want the shrouds and deadeyes to look “to scale,” you just about have to start with the foremost one on a mast and work your way aft. Shrouds (unless there’s an odd number of them in a gang) are set up in pairs, looped around the masthead. The loops (“collars”)are seized firmly around the masthead, with one loop stacked on top of another. The first pair to be rigged is the foremost pair on the starboard side; the collar forming that pair needs to be the one on the bottom of the stack. Then comes the foremost port pair, then the second pair on the starboard side, the second pair on the port side, etc.
That seems to have been a general rule throughout the sailing ship period.
There were, however, some changes in the handling of the odd-numbered shroud (if there was an odd number). James Lees’s Masting and Rigging of English Ships of War says quite emphatically that the aftermost shroud in the gang, sometimes called a “swifter,” was rigged individually with an eyesplice. I’ve seen other sources that say the foremost shroud in the gang was the one treated differently, and that it started on one side of the ship, went all the way around the masthead, and went down the other side. And the chief rigger at Mystic Seaport told me, many years ago, that the foremost shrouds on each side of the fore and main masts of the Charles W. Morgan were called “stiffeners,” and were set up individually, with eye splices, so they could be slacked off to give the lower yard a little more room to swing when the ship was working to windward. I’ve never encountered that explanation elsewhere, but it makes sense - and that gentleman certainly knew what he was talking about.
I’ve never had much success trying to set up deadeyes and lanyards off the model. The key to a nice-looking set of shrouds is to set them up taut - really taut. The only way I’ve ever been able to manage that is in the prototypical manner - by hauling them taut with the lanyards. You have to estimate how much the shroud is going to stretch when it’s hauled taut, and locate the deadeye accordingly. (You can cheat a little by leaving the seizing lines untrimmed until you’re almost finished, so you if you get the deadeye in the wrong place you can move it.)
I generally rig the lanyards before seizing the collar at the masthead, and deliberately leave a little slack in the shrouds when I set up the lanyards; putting the seizing on the collar then tightens them. Another trick that I’ve found useful is to leave off the bolster - the quarter-round piece of wood that sits on top of the trestletree at the masthead, for the upper end of the shroud to run over - until all the shrouds have been set up. I make the bolster out of a long (i.e., a couple of inches) stick, with a sharp point shaved on one end. Shoving the stick under the stack of shroud seizings tightens the shrouds a little more, and the bolster can be trimmed to length afterward. If the result is that the mast leans backward a tiny bit further than it should, so much the better; you can make the final adjustment when you set up the stay. (The stay, with the exceptions of some ships near the end of the sailing ship era, has to be rigged after the shrouds. The stay collar, running at a steep angle, has to rest outside/on top of the shroud collars.)
I don’t think it actually makes much difference which mast you rig first. (Exception: sometimes one encounters a rigging plan in which the lower end of the mizzen stay is secured to the mainmast a few feet up from the deck. In a case like that, the mast to which the lower end of the stay is fixed obviously has to be rigged first; you can’t allow a wiggling mainmast to slack off the mizzen stay.) The last few times I’ve done this sort of thing I started with the mainmast, because, being bigger, it’s a little easier. Then I rigged the mizzenmast because, having fewer shrouds, it breaks up the monotony a little. With the main and mizzen done, the end is in sight and I can usually muster up the energy to do the foremast.
In my experience, setting up the lower shrouds is the trickiest part of rigging a ship model. The kit manufacturers have, over the decades, tried all sorts of jigs and other dodges to make it easier, but I’ve never seen one that actually worked. (The system Heller used in its H.M.S. Victory, for instance, is pretty clever, but doesn’t work because it assumes the distance between the upper and lower deadeyes is constant. It isn’t. The aftermost deadeyes in a gang are considerably farther apart than the foremost ones, because the aftermost shroud runs at a considerable angle. The upper deadeyes of a Victory model rigged with a Heller jig would lie in a line that sloped down by the stern.) Model Shipways recently introduced a neat little adjustable jig that supposedly holds a pair of deadeyes a set distance apart while the lanyard is rigged. I haven’t tried that one; it may actually work. On the basis of what the Model Expo website says about it, though, it looks to me like there aren’t enough “distance settings” to cover the very slight differences in spacing encountered in a gang of shrouds on board a good-sized ship.
I’d be receptive to any new ideas on the subject, but so far I haven’t found an acceptable substitute for “doing it the old-fashioned way.”